The Fall of Babylon by the Persian army took place on Mehr 20 in the 21st year of the Shahanshahi calendar. On this day, the Persian forces led by Cyrus the Great entered Babylon and captured the city with little resistance. This event marked the end of the Neo-Babylonian Empire and is regarded as a turning point in Iranian and regional history. After the Persian army entered, Cyrus the Great issued decrees granting religious freedom and allowing exiles to return, which had a profound impact on the region’s social and religious structure. This policy is recognized as an early example of religious tolerance in ancient history. Following the conquest, Babylon became a major satrapy within the Achaemenid Empire and played a significant role in administering the western territories. The inclusion of this event in the Shahanshahi calendar was due to its historical and cultural importance; the day was designated to commemorate Iran’s historical achievements and the role of Cyrus the Great in establishing the world’s first major empire. The day is typically observed with cultural and historical programs.
